With development of an optical reading device using a line sensor including CCD (charge-coupled device) and an optical writing device using laser irradiation, a digital copier which creates a copy from digital image data appeared. A multi-function peripheral (MFP) having multiple functions, including a copy function, a fax function, a printer function, a scanner function, etc. is put in practical use with the development of the digital copier.
On the other hand, with evolution of the technology relating to the MFP, such as development of hard disk drive (HDD) with large storage capacity and low cost, improvement in the high-speed communication technology and the spread of networking technology, and improvement in the throughput of CPU and the technology of digital image data compression, the functions which are incorporated in the MFP are diversified. The way the MFP is used is also diversified.
For example, such diversified MFP may include: 1) a small-size MFP which is installed beside a PC enabling an operator on the PC to easily use one of the multiple functions including a copy function, a fax function, a printer function and a scanner function; 2) a medium-size MFP which is shared by a number of persons in a company section or department and provides additional functions, such as sorting, punching, stapling, and a certain amount of productivity; and 3) a large-sized MFP which has a high throughput and quality image output provided with various functions and is installed in a company or company section specializing the copy related business.
Although there are some functions which can be used in common for all of the MFP classes, specific functions are demanded for only one of the MFP classes while different functions are demanded for the other MFP classes. For example, for the large-size MFP, not only the post-processing functions, such as punching, stapling and sheet folding functions, but also the electronic filing function simultaneously with the copy function may be demanded. In contrast, for the small-size MFP, the high-quality image printing to recording sheets and the provision of Internet fax and PC fax functions are chiefly demanded for the purpose of personal use.
To meet such demands, the system incorporating the set of functions required for each MFP class was conventionally produced, sold and supplied to the diversified MFP market.
The importance of information in business is already known, and transferring information early and correctly with certainty and notifying information effectively and intelligibly are requested. The provision and merging of new functions are desired for the MFP which deals with digital image data.
Under such situations, the products are provided with multiple functions increasingly, the user is allowed to set up a large number of requests using an operation panel, and an image processor control unit which manages a large number of requests is demanded.
The middleware which will be mentioned hereinafter is implemented on a digital signal processor (DSP) in the MFP, for example. When compared with the hardware (ASIC), the middleware (DSP) enables one of various kinds of image processing programs to be implemented by exchanging the program and data with new ones.
However, as the variation of the image processing increases, the control unit which controls the DSP will have a complicated structure. The countermeasures for the image-processing control with which the specification change can be easily performed must be taken immediately and certainly in response to the specification change. Therefore, it is desired that the existing MFP is arranged to perform the image-processing control which is in conformity with various requests input from the operation panel, and to take countermeasures to the specification change flexibly.
However, the DSP is more expensive than the ASIC (application-specific integrated circuit), and the ASIC is used to take countermeasure to the image processing control in which the specification change does not happen seldom. The device which performs the image processing is selected depending on the usage of the image processing device, and a control unit which controls the image processing device is required.
The image processing which is currently demanded to be arranged in the MFP may include an illegal copy detection process and a bill recognition process. In recent years, similar to the demand for high quality of image, the demand for security is increasingly important. Installing the image recognition functions, such as the illegal copy detection function and the bill recognition function, in the image-processing device in the MFP is becoming the standard equipment.
The bill recognition process which is one of the recognition functions is important in order to inhibit copying of a bill and convert the corresponding image into a non-readable image if the illegal copying of a bill is detected.
Similar to the bill recognition, the illegal copy detection process is also important in order to detect the illegal copying and convert the corresponding image into a non-readable image. And the demand for the illegal copy detection function is diversified increasingly.
If the recognition or the detection is not performed correctly in the recognition process, the subsequent processes following the recognition process will not be performed. One of the reasons the recognition or the detection is not performed correctly may be the defect of the algorithm of the recognition process, which causes the failure of the recognition. Another of the reasons may be that the image-processing device which performs the recognition process does not function correctly and the recognition is impossible.
Some countermeasures that are to be taken when the image-processing device which performs the recognition process does not function correctly and a problem that the recognition is impossible arises are proposed. For example, Japanese Laid-Open Patent Application No. 2005-277841 discloses a method of detecting a device error from an image output from an image-processing device.
Japanese Laid-Open Patent Application No. 2005-045673 discloses a method of performing both detection of an error occurring in an image reader which reads input image data or an image output device which outputs image data, and error notification at a time.
Japanese Laid-Open Patent Application No. 01-125627 discloses a method of performing the device error checking in a hardware monitoring system for a device existing in a network.
However, the methods according to the related art require a lot of operations relating to the device error checking, and they are not appropriate for an image-processing device which operates on real time. In the case of the image-processing device which performs image processing only, it is adequate that the device error checking is performed once. If the image-processing device is used continuously and an error image is output due to the device error, a serviceman may be called so that hardware exchange is performed. After the hardware exchange is performed, the image-processing device can be used again.
However, in the case of the image-processing device which performs the recognition process, such as a bill recognition process or an illegal copy detection process, the print-out image is not influenced when the recognition process does not function correctly due to the device error. In such a case, the image-processing device may be used continuously even if the recognition process does not function correctly.